import java.util.*;

/*
 * public class ListNode {
 *   int val;
 *   ListNode next = null;
 *   public ListNode(int val) {
 *     this.val = val;
 *   }
 * }
 */

public class Solution2 {
    /**
     * 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
     *
     *
     * @param head ListNode类 the head
     * @return bool布尔型
     */
    public boolean isPail (ListNode head) {
        Stack<Integer> t1 = new Stack<>();
        ListNode cur = head;
        while( cur != null)
        {
            t1.push(cur.val);
            cur = cur.next;
        }
        while( head!= null)
        {
            if(head.val != t1.pop())
            {
                return false;
            }
            head = head.next;
        }
        return true;
    }}